Method of and apparatus for crushing rock



6- 1935- D. A. SILVER METHOD OF AND APPARATUS FOR CRUSHING ROCK Filed June 5 Patented Oct. 22, 1935 UNITED STATES METHOD OF AND APPARATUS FOR CRUSHING ROCK Drayton A. Silver, Goldendale, Wash.

Application June 5, 1933, Serial No. 674,382

'7 Claims.

This invention relates generally to the art of comminuting materials, and particularly to a rock crusher.

The main object of this invention is the evolution of a method of grinding materials.

The second object is to provide a rock crusher which will thoroughly crush a given quantity of rock in a minimum amount of time with the expenditure of a minimum amount of power without being destructive to the apparatus itself.

The third object is to crush rock in a natural mannerthat is by using the larger pieces of rock to crush the smaller pieces instead of obtaining the crushing action at the expense of a wearing action which is present in a large degree in existing devices.

These, and other objects, will become more apparent from the specification following as illustrated in the accompanying drawing, in which:

Fig. 1 is a perspective view of the device with parts broken away in section.

Fig. 2 is a section taken along the line 2--2 in Fig. 1.

Fig. 3 is a somewhat diagrammatic section taken along the line 3-3 in Fig. 1.

Fig. 4 is a section taken along the line 4-4 in Fig. 1.

Fig. 5 is a section taken along the line 5-5 in Fig. 1.

Fig. 6 is a section taken along the line 63 in Fig. 1.

Similar numbers of reference refer to similar parts throughout the several views.

Referring in detail to the drawing, the device consists of a conveyor l0 provided with heavy flights H, and preferably driven from its upper end by a gear |2 through a shaft |3 while its lower end passes around the idler sprockets I4 on the shaft l5. The sides of the conveyor It are closed by the sides l6 and [1. The lowermost portion of the sides l6 and I! is joined by a curved bottom l8 around which the flights swing as they pass around the idler sprockets I4.

Between the sides Hi and I1 and connecting with the curved bottom I8 is a sloping plate l9 upon which is placed an anvil composed of a plurality of spaced bars 25 whose interstices become filled with particles 2| of crush rock.

The conveyor H) is steeply inclined, being almost vertical, and having under its discharge side at the upper end thereof, an inclined chute 22 which carries the pieces of rock 23 laterally and discharges them into the sloping screen 24 provided with perforations 25.

The materials which do not pass through the screen 24 are returned by means of a deflecting plate 26 through an opening 21 in the side I6 from whence they will fall upon a deflector plate 28 and be directed against the upwardly traveling rocks 23 on the flights I finally striking the anvil bars 20 with great force, being further reduced in size as the result thereof, after which they again start on the upward Journey on the conveyor l0.

Those particles which pass through the perforations 25 in the screen 24 are collected in the chute 29 and carried by a duct 29A into the concentric screens 33, 3| and 32 which are supported by the spider 33 on the shaft 34, to which motion is imparted by the chain 35 which passes around the sprocket 36.

The materials 31 are delivered to the interior of the revolving screen 30, together with water which is admitted through a pipe 38 under the control of a valve 39. The particles 4|] which pass through the screen 30 are subjected to a screening action on the screen 3|, and the particles 4! are now passed over the screen'32 the resulting fine materials 42 being carried away through a collector trough 43 to a comminuting machine or storage bin (not shown). Those materials 31, 4E] and 4| which pass over the ends of their respective screens 30, 3| and 32 enter the funnel 44 and pass through the upright pipe 45 to the upper end of the anvil bars 20.

The purpose for separating the bars 20 is to make the top surface of the anvil self-sharpening thereby greatly improving the crushing and grinding action.

It can be seen from the foregoing that rocks passing through this machine will be subjected to a violent crushing by contact with other rocks,

and also by contact with the heavy conveyor flights H and the anvil bars 20 under the force of gravity, and that all of the action employed in existing forms of crushers which is so destructive to the mechanism itself is entirely eliminated.

It can also be seen that the materials will pass through the machine as often as required to reduce them to a given degree of fineness without attempting to obtain the full reduction simultaneously, thereby greatly reducing the wear and tear on the parts, the power consumed and at the same time maintaining the maximum capacity for the machine.

Furthermore, water is introduced only at the latter portion of the operation and in a relatively small quantity, the purpose being to minimize metals are held in suspension making it extremethe amount of loss due to the fine gold being held in suspension in the muddy water. In other words, in ordinary crushing machines in order that all of the material may be ground to a desired fineness a large portion of it is ground too fine, and these fine particles of rock and precious ly diflicult to recover the metals from the solution.

I am aware that many methods have beenem ployed'in the comminuting of materials and that many forms of apparatus have been employed in the practice of these methods, it is therefore not my intention to cover all formsand modifications of such but I do intend to cover all such modifications as fall fairly within the appended claims.

I claim:

1. A method of grinding materials consisting of progressively elevating a mixture of coarse and fine materials in stream formation, then segregating the coarsest of said'materials and discharging same against said ascending stream for the pur- 'pose'of further reducing the size of the pieces in the upwardly moving stream and in the downwardly moving stream and returning all of said 7 reduced portions to said upwardly moving stream. 7

2. A rock crusher having in combination a rock elevating conveyor having a segregating screen at the upper discharge end thereof, achute by 'means of which the coarser pieces of rock from said screen will be projected against the upwardly moving side of said conveyor, a revolving screen having an inlet chute for taking the finer materials passing through'said segregating screen, a second chute adapted to withdraw the finest portions from said revolving screen anda third chute for returning the coarser portion from said revolving screen to said conveyor.

3. A rock crusher having in combination a rock elevating conveyor, means for segregating the large pieces of rock at the top of said conveyor and discharging same against the upwardly movthe fines from said machine, as rapidly as they are produced comprising a system of screens whereby the partially crushed materials are segregated and the coarser portions thereof returned to the intake oi said conveyor.

4. A crusher as described in claim 2 including an anvil at the bottom of said elevator against which the coarser pieces of rock being returned to said crusher are directed.

5. A rock crusher havingin combination an inclined elevating conveyor having a screen at the upper end thereof including a conduit for projecting the coarsest material which passes over said screen against the upwardly moving conveyor flights, a second chute for receiving the materials which pass through said screen, a revolving screen fed by said second chute, a chute for collecting the fines from said revolving screen and a third chute taking the coarser material from said revolving screen and returning same to said conveyor. v

6. The crusher described in claim 5, together with an anvil disposed at the lower end of said a conveyor against which the intermediate grades of material may be projected and means for introducing water to said crusher by way of the revolving screen.

'7. A rock crusher having in combination an inclined conveyor, a collector disposed at. the bottom of the conveyor constituting a loading point thereof, the upper end of said conveyor constituting its discharge end, an inclined'anvil at the loading point of said conveyor from which materials can pass into said collector, said anvil being at the lower end of the upwardly traveling run of the conveyor, said anvil comprising a plurality of spaced bars along whose uppermost edges ma terials may pass into the collector where they will be packed up by said conveyor, a plurality of screens having means for projecting its coarsest materials againstthe upwardly moving portion of the conveyor, another of said screens serving to withdraw the fines from the crusher and to return the coarser portions to the conveyor.

DRAYTON A. SILVER. 

